Pump



. NOV. 17, 1931. L M PERSQNS 1,832,788

PUMP

original Filed July 1s, 1925 2 sheets-sneer 1 Nov. 17, 1931. L. M.PERsoNs 1,832,788

PUMP

Original Filed July 13, 1925 2 Sheets-Sheet 2 Patented Nov. 17, 1931UNITED STATES PATENT OFFICE LAWRENCE M. PERSONS, OF CHICAGO, ILLINOIS,ASSIGNOB TO COOK ELECTRIC COH- PANY, OF CHICAGO, ILLINOIS,!A CORPORATIONF ILLINOIS PUMP Original application led July 13, 1925, Serial No.43,084. 'Divided and this application led February 1, 1926. Serial No.85,370.

My invention relates to systems for pumping liquid into a tank orreceptacle and more particularly to a motor driven pump, hav ing as oneof its characteristics the abillty to operate automatically upon thewithdrawal of liquid from the tank or receptacle.

This application is a division of my copending application, Serial No.43,064, filed July 13, 1925.

In the automatic operation of a motor driven pump, means are usuallyemployed to control the circuit to the motor according to some operatingcondition of the pump.

' This means may comprise a float control switch mechanism arranged toclose the circuit when the liquid in the receptacle falls below apredetermined low level. It will be seen that the operation of the pumpis, therefore, automatic and that the pump will start pumping when theliquid therein reaches a predetermined low level. It has been found,however, that the lowerin of the liquid level is not always the result oan operating condition, inasmuch as leaks frequently occur in the pipeline between the receptacle and the point where the liquid is consumed.On the other hand, in oil burning systems, the oil burner often causesan abnormal drain on the receptacle when the needle valve of the floatmechanism of the burner fails to work.

If the float controlled switch mechanism closes the circuit when theliquid level lowers in the receptacle, the pump will continue to feedthe liquid to the receptacle until the level is again restored, butshould a leak occur as stated,lor should the oil burner place anoverload on the pump, this level will not be restored automatically andit is possible for the pump to continue pumping and empty the bulksupply tank of the oil burning system v ties of the prior art devices bythe provision of a safety means of simplicity, which is accurate andefficient in operation and devoidof intricate mechanism which isapt torequire constant attention and frequent repair.

In carrying out my invention I embodied the aforesaid safety meanspreferably within a small receptacle associated with the pump, so thatwhen the fuel is entirely Withdrawn from the receptacle, or is withdrawnbelow a predetermined low level, as the case may be, as the result of anoverload on the pump, the latter is immediately rendered inoperative. l

In this respect my invention is an improvement over a co-pendingapplication, Serial No. 30,578, filed May 15, 1925, in' which there hasbeen disclosed and broadly claimed, a pump of the type herein shown, andin'which is disclosed a novel form of structure for disabling theoperation should the liquid bewithdrawn therefrom at a rate greater thanwhat is normally controlled by the burner. The present inventionprovides a very simple and efficient means for accomplishing thisresult, beingin the form of a single float capable of opening thecircuit of the motor when in its upper or lower positions.v Hence, theioat i serves to disable the operation of the pump when the fuel in thesaid receptacle has reached a predetermined high level, to start thepump when the fuel drops below this high level, and to stop the pumpwhen the fuel has been withdrawn below a predetermined low level. Thelatter may be the result of the liquid being drawn from the receptacleor pump at a rate greater than the normal consumption by the oil burner,or whatever liquid consuming device that is employed.

Further objects and advantages of my invention will be apparent from thefollowing description when taken in connection with the-accompanyingdrawings forming apart hereof.

In the drawings:

Figure 1 is a view, partlylin vertical section and partly in elevation,vvof a pump embodying my invention;

Fig. 2 is a diagrammatic'iview of an oil burning system for the purposeofillustrating one of the many different systems that may employ thispump;

Fig. 3 is an enlarged detail elevational view I of the switch mounting;

Fig. 4 is a sectional view taken on line 4-4 of Fig. 3; and

Fig. 5 is a horizontal sectional View of one end of the mercury switchillustrating the electrodes bridged by a body of mercury.

In the operation shown in Fig. 1 the oil or liquid from the storage tank5 or other source of supply is drawn through a suction pipe 6 by meansof a pump 7 and is fed through an outlet pipe 8 into a tank orreceptacle 10. Pump 7 is driven by an electric motor 9.

The automatic safety control disclosed herein comprises a iioat 12mounted in any suitable manner within the tank. as for instance on a rod13, so that it will be guided on the rod as it moves up and down. Anelectric switch 14 is actuated by float 12 to cause the automaticstarting and stopping operations above set forth.

Switch 14 is provided in the motor circuit and is preferably of themercury type, having a pair of electrodes adapted to be bridged by abody of mercury when the switch is in closed position. A dependingbracket 15 is adapted to be fastened to the underside of the top of tank10 by a screw 16. Sides 17 of depending bracket 15 are apertured at 18to receive the pivotal lugs 19, extending transversely from the sides ofa carriage 20 on which mercury switch 14 is disposed. As illustrated indetail in Fig. 3, the carriage 20 comprises a plate on which side clips21 are mounted to receive mercury switch 14.

Said side clips 21 have lugs 22 struck up from their sides to clipconductor carrying members 24 at the sides so that the lead in wires ofthe mercury switch may be brought forwardly to the front and connectedto the electrodes of the mercury 2, as illustrated at 25 in Fig. 3.

The opposite ends of these conductors are protected by flexible armouredcoverings 26 which are fastened into an insulation collar 27. Bracket 15may be provided with a dependin detacha le plug connection 29 for themotor conductors 30 and 31 extending upwardly into the motor housingthrough a sleeve of insulation 32.

One end of plate 20 extends integrally downwardly at a sli ht angle tocarry a buffer 33, which is adapte to be engaged by float 12 when thefloat is raised to its maximum high level for the purpose of opening thecircuit to the motor 9. The opposite end. of plate 2O is furnished withan arm 35. The upper end of rod 13 is bent substantially at a rightangle as indicated at 36 to pivotally connect to eX tension 35 at 37. Acollar 38 is fastened to stem 13 adjacent to the lower end of the stem.

In the normal operation of the device the arm 28 for carrying collar 27and liquid will be withdrawn through the deliv ery pipe or outlet 45,thereby causing the liquid in receptacle 10 to be lowered below lineA-B, illustrated in Fig. 1. Float 12 will move with the liquid andrelease the switch 14 from its open position by disengaging the buffer33. The switch is then permitted to tilt in the direction .of thebuffer, by gravity, about its pivots 19. The circuit to the motor isthereby closed and the pump 7 is operated to draw liquid out of thestorage tank 5 and t0 feed it through pipe 8 into receptacle 10.

If the additional liquid thus supplied permits the level A-B to beyagain obtained, the switch 14 is tilted upwardly to open position bylfloat 12, engaging the buffer 33 and moving it upwardly. If, however,after continuous pumping of additional liquid through pipe 8 into tank10 the level A-B is not obtained, but, on the contrary, the liquid feedsthrough the delivery pipe faster than it is fed into tank 10, the liquidlevel will continue to lower iioat 12 until the float engages lug 38.The weight of the float 12 against lug 38 is sufficient to force stem 13downward-- ly, thereby exerting a downward pull on carriage extension 35to cause pivoting of switch 14 in this direction; that is, in its openposition. The circuit to the motor is thereby broken and the pump 7 istemporarily disabled.

A further feature of my invention resides in the provision of animproved resetting mechanism for operating the pump after it has beendisabled by iioat 12 falling to the bottom of the receptacle 10 to openswitch 14. With the liquid entirely withdrawn from re-Y ceptacle 10,this resetting mechanism functions to lift iioat 12 upwardly a shortdistance so as to relieve the stem 13 from the i.

weight of the float, as at 38, and thereby permit the switch itself topivot by gravity to closed position. The circuit to the motor will thenbe closed. This mechanism may be employed to hold float 12 in theposition removing its weight from stem 13 until enough liquid has beenpumped into receptacle 10 to continue holding the float away from lug38.

Said mechanism may comprise a. vertical rod 4() extending into tank 10with its lower end bent at right angles as indicated at 41 to a pointbelow float 12. The other end of rod 40 projects through the top ofreceptacles 10 and ma be provided with a knob 42. A stop 43 confiynes acoil spring 44 between it and the underside of the top of tank 10, sothat ro'd 40 will itself snap into normal position when released at theknob 42. It is apparent that by manually engaging knob 42 and lift- .a

ing rod 41 upwardly, the float 12 when in its dotted line position asshown in Fig. 1. and lift it upwardly a short distance.

From. the foregoing description, it will be readily apparent that anabnormal demand by the burner or by a leak in the fuel line willinmediately cause the float to open the switch and break the circuit tothepmotor, and to thereby prevent a serious conHagration of fuel thatmay Hood the basement Hoor where the burner is located. Such anarrangment is particularly unique in cases where the owner of a buildingmay wish to leave the remises for several days and may then set t e roomthermostat (not shown) to maintain a certain temperature whereby toprevent the pipes of the house from freezing. The Board of Underwritershas found that it is during such periods of absence from the premisesthat leaks occur in the pipe between the burner and the receptacle 10and Hood the basement and cause serious fires because these leaks atsuch times usually go unnoticed too long.

I wish to emphasize the fact that the feature of providing a tripleacting Hoat controlling mechanism capableof'shutting down the supply ofliquid to any type of receptacle may take many forms other than thatillustrated and described herein and that the invention is not limitedto oil burning systems.

Various other embodiments and modificaf tions of my invention will beapparent to those skilled in the art, and, consequently, I do notintendto be limited to the details herein described and illustrated.

1. The combination with a motor driven pump, having a switch forcontrolling the circuit to the motor, of a Hoat for actuating saidswitch, larranged so that the switch will be open when the Hoat is inraised position, and will be closed when the Hoat is in intermediateposition, and will be opened when the float is in lowered position.

2. In a pumping apparatus, the combination of a source of supply, areceptacle. a motpr driven pump for pumping liquid from the source ofsupply into said receptacle, a switch for controlling said motor, and aHoat in the receptacle, which is adapted to open the switch when theliquid reaches an upper level, to close the switch when the liquidreaches an intermediate level, and to again open the switch when theliquid reaches a lower level.

3. The combination with a supply tank, of a motor driven pump forpumping liquid from a storage tank to the supply tank, a float in saidsupply tank, a switchfor controlling the motor, and operativeconnections between the float and the switch whereby the switch will beswung to open position when the Hoat rises and will be swung to closedposition when the Hoat moves downwardly to a predetermined position andthe switch will be again swung to open position when the float movesdownwardly beyond said predetermined positlon. v

4. The combination with a receptacle having a Hoat therein, of a switchadapted to be actuated by the Hoat, said Hoat having operativeconnections with the switch whereby the switch will be automaticallythrown to closed position when the Hoat is at a predetermined point andthe switch will be thrown to open position if the Hoat moves above 4orbelow said predetermined point, substantially as described.

5. The combination with a quick make and break switch, of an operatingmember and connections between the switch and operating member wherebythe switch will be opened when the operating member is in one position,will be closed when the operating member moves a predetermined distanceand will again be opened when the operating member is moved a furtherpredetermined distance in the same direction.

6. The combination with an electric switch, of an operating member andconnections between the operating member and the switch, whereby theswitch will be opened when the operating member is in raised position,will be closed when the operating member is in intermediate position,and' will again be opened when the operating member is 'in loweredposition.

7 The combination with a receptacle, of an electrically driven pump forsupplying liquid to said receptacle, a switch in the electric circuit ofsaid pump, and a triple acting Hoat in said receptacle for opening andclosing said circuit when in different predetermined positions.

8. The combination with a receptacle, of electrically controlled meansfor supplying liquid to said receptacle, a switch in the electriccircuit of said means, a rod suspend-ed from one end of said switch, anda Hoat movably guided along said rod, said Hoat serving to open saidswitch by the weight of said Hoat on said rod when said float is in apredetermined low position, and to open said switch by the movement ofsai-d Hoat upwardly along said rod when said Hoat is in a predeterminedupper position.

9. The combination with a receptacle and electrically controlled meansfor supplying lquid to said receptacle, of a switch in the circuit ofsaid means, a Hoat movably guided in said receptacle adapted when in apredetermined upper position to open said switch, and means for limitingthe downward movement of said float whereby the weight of said floatagainst said means serves to open Said switch.

10. The combination with a pump, of electrical means for operating saidpump, a receptacle for receiving the liquid supplied by said pump, atiltable mercury switch in circuit with said means, and a Hoat fortilting said mercury switch to open circuit position when the liquidHows from said receptacle in excess of a predetermined rate, said Hoatbeing arranged also to tilt said mercury switch to open circuit positionwhen the lquid reaches a predetermined high level in said receptacle.

11. The combination with a receptacle, of a motor driven pump forsupplying liquid to said receptacle, a switch in circuit with said motordriven pump, a float connected to said switch adapted to open saidswitch when the liquid drops to a. predetermined level in saidreceptacle, and means for temporarily disabling the action of said floatwhereby to close said switch when Said float is at said predeterminedlevel.

12. In a device of the class described: a. container adapted to hold aliquid, a float therein, an electric switch, connecting mechanismbetween the float and the switch for opening the switch by the movementof the float in one direction and 'for closing the switch by a movementof the float in the opposite direction, and for again openin the switchby the continuing movement o the ioat in the last specified direction.

18. In a device of the class described: a container adapted to hold aliquid, a, float therein, a movable member, connecting mechanism betweenthe lo'at and the movable member, for moving said member to one postionby the movement of the float in one direction, and for moving saidmember to another position by the movement ofV the float in the oppositedirection, and for moving said member to its 4first-mentioned positionby continued movement of the oat vin the last specified direction.

14. In a device of the class described: an electric switch within anelectric circuit, mechanism for operating said switch and a floatconnected to said mechanism for actuating said mechanism, said mechanismhaving two operative positions Vfor opening the switch circuit and athird operative position for closing sa'id switch circuit.

15. In a device of the class described: a

- tiltable electric switch within an electric circuit, said switchhaving two operative positions for breaking the circuit through saidtiltablc switch,""a third o erative position for completing the circuitt rough said tiltable switch, and a float adapted to actuate the switchfor making and breaking a circuit in said three operative positions.

In witness whereof, I have hereunto subscribed my name.

LAWRENCE M. PERSONS.

